Do heavier cars go faster downhill?
Believe it or not, when objects roll downhill, it's not their weight or size that determines their speed—it's how their weight is distributed.
The amount of energy it takes to move a car from one point to another is highly dependent on the mass, so the lighter the vehicle, the less energy it takes to move it from one place to another. A lighter car is also a faster car.
The change in speed on slopes is due to gravity. When going downhill, objects will accelerate (go faster), and when going uphill they will decelerate (slow down). On a flat surface, assuming that there is little friction, they will then maintain a constant speed.
Weight affects speed down the ramp (the pull of gravity), but it's the mass (and friction) that affects speed after a car leaves the ramp. Heavier cars have more momentum, so they travel further, given the same amount of friction.
Heavier riders can descend faster than light riders because heavier riders don't have significantly more volume/surface area than their lighter counterparts, despite possibly major differences in weight.
You should find that a solid object will always roll down the ramp faster than a hollow object of the same shape (sphere or cylinder) — regardless of their exact mass or diameter. This might come as a surprising or counterintuitive result!
The purpose of "downshifting", or shifting the transmission down from a higher gear to a lower gear, is so that a driver can accelerate their car as fast as possible when exiting a corner that they had to slow down for.
Use lower gears to go downhill
When you start to head back downhill, use your engine and transmission to slow the car down instead of the brakes. Shift to a lower gear before you start heading downhill, as this will help slow down the car without you having to ride the brakes, says the National Park Service.
After a two sample t-test, we find that heavier rolling objects have a statistically faster clear time for a given inclined plane in comparison to lighter rolling objects. In addition, heavier objects will be more resistant to the effects of air resistance and rolling resistance.
Given two objects of the same size but of different materials, the heavier (denser) object will fall faster because the drag and buoyancy forces will be the same for both, but the gravitational force will be greater for the heavier object.
Does weight of car affect suspension?
Increased weight (typically seen with rear sagging caused by heavy loads) decreases the available compression travel for normal suspension operation thus increasing the frequency and severity of contact with the bump stops.
When a car is on a ramp, a component or part of the force of gravity acts parallel to the ramp, causing the car to speed up, or accelerate down the ramp. This acceleration is not as great as when the car falls straight down since part of the gravitational force is also holding the car against the ramp.
Going downhill converts that potential energy to kinetic energy; the car or bicycle will start going faster and faster unless you use the brakes (converting kinetic energy to heat) or use some sort of regenerative braking (hybrid cars).
As you go downhill, your vehicle's speed increases. Never exceed the maximum safe speed on a downgrade. Downshift to a low gear before staring down a grade. You must use the braking effect of the engine to control your speed on downgrades.
What is the purpose of downshifting? Downshifting is necessary in order to put the car in the optimal gear to maximize acceleration when the time comes to squeeze on the throttle after we have exited a corner.
As the angle increases, the component of force parallel to the incline increases and the component of force perpendicular to the incline decreases. It is the parallel component of the weight vector that causes the acceleration. Thus, accelerations are greater at greater angles of incline.